edu.rit.draw.item

Class Line

java.lang.Object

edu.rit.draw.item.DrawingItem

edu.rit.draw.item.OutlinedItem

edu.rit.draw.item.Line

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable

public class Line
extends OutlinedItem
implements java.io.Externalizable

Class Line provides a DrawingItem that consists of one or more straight line segments. The line may have an Arrow at either or both ends. The line may have sharp corners or round corners. The line has an outline but no filled interior.

If the line has round corners, the round corner distance gives the distance from where the (sharp) corner would normally be to the starting and ending points of the round corner arc, as shown in the adjoining diagram. (The round corner distance is d.) A round corner distance of 0 results in a sharp corner. In a particular line, the same round corner distance is used for every corner; that is, either all the corners are sharp or all the corners are rounded the same amount. Different lines can have different round corner distances.

The static defaultStartArrow(), defaultEndArrow(), and defaultRound() methods are provided to set the default starting arrow, ending arrow, and round corner distance. If the starting arrow, ending arrow, or round corner distance is not specified, the current default starting arrow, ending arrow, or round corner distance is used.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static Arrow	NORMAL_END_ARROW The normal ending arrow: None.
static double	NORMAL_ROUND The normal round corner distance (0), signifying sharp corners.
static Arrow	NORMAL_START_ARROW The normal starting arrow: None.

Fields inherited from class edu.rit.draw.item.OutlinedItem

NORMAL_OUTLINE

Constructor Summary

Constructors

Constructor and Description
Line() Construct a new line.
Line(Line theLine) Construct a new line with the same points, outline, starting arrow, ending arrow, and round corner distance as the given line.

Method Summary

Modifier and Type	Method and Description
Line	add() Add this line to the end of the default drawing's sequence of drawing items.
Line	add(Drawing theDrawing) Add this line to the end of the given drawing's sequence of drawing items.
Line	addFirst() Add this line to the beginning of the default drawing's sequence of drawing items.
Line	addFirst(Drawing theDrawing) Add this line to the beginning of the given drawing's sequence of drawing items.
Line	by(double dx, double dy) Add a line segment to this line.
Line	by(Size theSize) Add a line segment to this line.
Line	clear() Clear this line.
static Arrow	defaultEndArrow() Returns the default ending arrow.
static void	defaultEndArrow(Arrow theArrow) Set the default ending arrow.
static double	defaultRound() Returns the default round corner distance.
static void	defaultRound(double theRound) Set the default round corner distance.
static Arrow	defaultStartArrow() Returns the default starting arrow.
static void	defaultStartArrow(Arrow theArrow) Set the default starting arrow.
void	draw(java.awt.Graphics2D g2d) Draw this drawing item in the given graphics context.
Arrow	endArrow() Returns this line's ending arrow.
Line	endArrow(Arrow theArrow) Set this line's ending arrow.
Line	hby(double dx) Add a horizontal line segment to this line.
Line	hby(Size theSize) Add a horizontal line segment to this line.
double	height() Returns the height of this drawing item's bounding box.
Line	hto(double x) Add a horizontal line segment to this line.
Line	hto(Point thePoint) Add a horizontal line segment to this line.
Point	nw() Returns the northwest corner point of this drawing item's bounding box.
Line	outline(Outline theOutline) Set this line's outline.
void	readExternal(java.io.ObjectInput in) Read this line from the given object input stream.
double	round() Returns this line's round corner distance.
Line	round(double theRound) Set this line's round corner distance.
Size	size() Returns the size of this drawing item's bounding box.
Arrow	startArrow() Returns this line's starting arrow.
Line	startArrow(Arrow theArrow) Set this line's starting arrow.
Line	to(double x, double y) Add a line segment to this line.
Line	to(Point thePoint) Add a line segment to this line.
Line	vby(double dy) Add a vertical line segment to this line.
Line	vby(Size theSize) Add a vertical line segment to this line.
Line	vto(double y) Add a vertical line segment to this line.
Line	vto(Point thePoint) Add a vertical line segment to this line.
double	width() Returns the width of this drawing item's bounding box.
void	writeExternal(java.io.ObjectOutput out) Write this line to the given object output stream.

Methods inherited from class edu.rit.draw.item.OutlinedItem

defaultOutline, defaultOutline, outline

Methods inherited from class edu.rit.draw.item.DrawingItem

boundingBox, c, e, n, ne, s, se, sw, w

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

NORMAL_START_ARROW

public static final Arrow NORMAL_START_ARROW

The normal starting arrow: None.

NORMAL_END_ARROW

public static final Arrow NORMAL_END_ARROW

The normal ending arrow: None.

NORMAL_ROUND

public static final double NORMAL_ROUND

The normal round corner distance (0), signifying sharp corners.

See Also:

Constant Field Values

Constructor Detail

Line

public Line()

Construct a new line. The line has no points initially. The default outline, starting arrow, ending arrow, and round corner distance are used.

Line

public Line(Line theLine)

Construct a new line with the same points, outline, starting arrow, ending arrow, and round corner distance as the given line.

Parameters:

theLine - Line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theLine is null.

Method Detail

defaultStartArrow

public static Arrow defaultStartArrow()

Returns the default starting arrow.

Returns:

Default starting arrow.

defaultStartArrow

public static void defaultStartArrow(Arrow theArrow)

Set the default starting arrow. Before calling this method the first time, the default starting arrow is Arrow.NONE.

Parameters:

theArrow - Default starting arrow.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theArrow is null.

defaultEndArrow

public static Arrow defaultEndArrow()

Returns the default ending arrow.

Returns:

Default ending arrow.

defaultEndArrow

public static void defaultEndArrow(Arrow theArrow)

Set the default ending arrow. Before calling this method the first time, the default ending arrow is Arrow.NONE.

Parameters:

theArrow - Default ending arrow.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theArrow is null.

defaultRound

public static double defaultRound()

Returns the default round corner distance. A value of 0 signifies sharp corners.

Returns:

Default round corner distance.

defaultRound

public static void defaultRound(double theRound)

Set the default round corner distance. A value of 0 signifies sharp corners. Before calling this method the first time, the default round corner distance is 0.

Parameters:

theRound - Default round corner distance.

Throws:

java.lang.IllegalArgumentException - (unchecked exception) Thrown if theRound is less than 0.

size

public Size size()

Returns the size of this drawing item's bounding box.

Overrides:

size in class DrawingItem

Returns:

Size.

width

public double width()

Returns the width of this drawing item's bounding box.

Specified by:

width in class DrawingItem

Returns:

Width.

height

public double height()

Returns the height of this drawing item's bounding box.

Specified by:

height in class DrawingItem

Returns:

Height.

nw

public Point nw()

Returns the northwest corner point of this drawing item's bounding box.

Specified by:

nw in class DrawingItem

Returns:

Northwest corner point.

outline

public Line outline(Outline theOutline)

Set this line's outline.

Overrides:

outline in class OutlinedItem

Parameters:

theOutline - Outline, or Outline.NONE.

Returns:

This line.

clear

public Line clear()

Clear this line. All of this point's line segments are removed.

Returns:

This line.

to

public Line to(double x,
               double y)

Add a line segment to this line. The new endpoint is (x, y). If this line has no line segments, the to() method specifies this line's starting endpoint.

Parameters:

x - Endpoint's X coordinate.

y - Endpoint's Y coordinate.

Returns:

This line.

to

public Line to(Point thePoint)

Add a line segment to this line. The new endpoint is thePoint. If this line has no line segments, the to() method specifies this line's starting endpoint.

Parameters:

thePoint - Endpoint.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if thePoint is null.

hto

public Line hto(double x)

Add a horizontal line segment to this line. The new endpoint is (x, previous endpoint's Y coordinate).

Parameters:

x - Endpoint's X coordinate.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if there is no previous endpoint.

hto

public Line hto(Point thePoint)

Add a horizontal line segment to this line. The new endpoint is (thePoint's X coordinate, previous endpoint's Y coordinate).

Parameters:

thePoint - Endpoint.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if thePoint is null. Thrown if there is no previous endpoint.

vto

public Line vto(double y)

Add a vertical line segment to this line. The new endpoint is (previous endpoint's X coordinate, y).

Parameters:

y - Endpoint's Y coordinate.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if there is no previous endpoint.

vto

public Line vto(Point thePoint)

Add a vertical line segment to this line. The new endpoint is (previous endpoint's X coordinate, thePoint's Y coordinate).

Parameters:

thePoint - Endpoint.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if thePoint is null. Thrown if there is no previous endpoint.

by

public Line by(double dx,
               double dy)

Add a line segment to this line. The new endpoint is (previous endpoint's X coordinate + dx, previous endpoint's Y coordinate + dy).

Parameters:

dx - X distance.

dy - Y distance.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if there is no previous endpoint.

by

public Line by(Size theSize)

Add a line segment to this line. The new endpoint is (previous endpoint's X coordinate + theSize.width(), previous endpoint's Y coordinate + theSize.height()).

Parameters:

theSize - Distance.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theSize is null. Thrown if there is no previous endpoint.

hby

public Line hby(double dx)

Add a horizontal line segment to this line. The new endpoint is (previous endpoint's X coordinate + dx, previous endpoint's Y coordinate).

Parameters:

dx - X distance.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if there is no previous endpoint.

hby

public Line hby(Size theSize)

Add a horizontal line segment to this line. The new endpoint is (previous endpoint's X coordinate + theSize.width(), previous endpoint's Y coordinate).

Parameters:

theSize - Distance.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theSize is null. Thrown if there is no previous endpoint.

vby

public Line vby(double dy)

Add a vertical line segment to this line. The new endpoint is (previous endpoint's X coordinate, previous endpoint's Y coordinate + dy).

Parameters:

dy - Y distance.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if there is no previous endpoint.

vby

public Line vby(Size theSize)

Add a vertical line segment to this line. The new endpoint is (previous endpoint's X coordinate, previous endpoint's Y coordinate + theSize.height()).

Parameters:

theSize - Distance.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theSize is null. Thrown if there is no previous endpoint.

startArrow

public Arrow startArrow()

Returns this line's starting arrow.

Returns:

Starting arrow.

startArrow

public Line startArrow(Arrow theArrow)

Set this line's starting arrow.

Parameters:

theArrow - Starting arrow.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theArrow is null.

endArrow

public Arrow endArrow()

Returns this line's ending arrow.

Returns:

Ending arrow.

endArrow

public Line endArrow(Arrow theArrow)

Set this line's ending arrow.

Parameters:

theArrow - Ending arrow.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theArrow is null.

round

public double round()

Returns this line's round corner distance. A value of 0 signifies sharp corners.

Returns:

Round corner distance.

round

public Line round(double theRound)

Set this line's round corner distance. A value of 0 signifies sharp corners.

Parameters:

theRound - Round corner distance.

Returns:

This line.

Throws:

java.lang.IllegalArgumentException - (unchecked exception) Thrown if theRound is less than 0.

add

public Line add()

Add this line to the end of the default drawing's sequence of drawing items.

Overrides:

add in class OutlinedItem

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if there is no default drawing.

See Also:

Drawing.defaultDrawing()

add

public Line add(Drawing theDrawing)

Add this line to the end of the given drawing's sequence of drawing items.

Overrides:

add in class OutlinedItem

Parameters:

theDrawing - Drawing.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theDrawing is null.

addFirst

public Line addFirst()

Add this line to the beginning of the default drawing's sequence of drawing items.

Overrides:

addFirst in class OutlinedItem

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if there is no default drawing.

See Also:

Drawing.defaultDrawing()

addFirst

public Line addFirst(Drawing theDrawing)

Add this line to the beginning of the given drawing's sequence of drawing items.

Overrides:

addFirst in class OutlinedItem

Parameters:

theDrawing - Drawing.

Returns:

This line.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if theDrawing is null.

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Write this line to the given object output stream.

Specified by:

writeExternal in interface java.io.Externalizable

Overrides:

writeExternal in class OutlinedItem

Parameters:

out - Object output stream.

Throws:

java.io.IOException - Thrown if an I/O error occurred.

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException

Read this line from the given object input stream.

Specified by:

readExternal in interface java.io.Externalizable

Overrides:

readExternal in class OutlinedItem

Parameters:

in - Object input stream.

Throws:

java.io.IOException - Thrown if an I/O error occurred.

java.lang.ClassNotFoundException - Thrown if any class needed to deserialize this line cannot be found.

draw

public void draw(java.awt.Graphics2D g2d)

Draw this drawing item in the given graphics context. This method is allowed to change the graphics context's paint, stroke, and transform, and it doesn't have to change them back.

Overrides:

draw in class DrawingItem

Parameters:

g2d - 2-D graphics context.